Flexible cover forming machine



Nov. 23, 1948. A. vlscHER, JR

FLEXIBLE COVER FORMING MACHINE Filed Aug. 1, 1945 NOV. 23, 1948.A#VlsqgplER' JR v 2,454,758v

FLJIXIBLE` COVER FRMING MACHINE Filed Aug. l, 1945' 7 Sheets-Sheet 2Nov. 23, 1948. A, VISCHER, JR f 2,454,758

FLEXIBLE covER FORMING MACHINE Filed Aug. 1, 1945 7 sheets-sheet 3 NOV.23, 1948. A VlscHER, JR 2,454,758

FLEXIBLE COVER FORMING MACHINE Filed Aug. l, 1945 v 7 Sheets-Sheet 4Nov. 23, 1948. A. vlscHER, JR

FLEXIBLE COVER FORMING MACHINE Filed Aug. l, 1 945 '7 sheets-sheet 5Www] NOV. 23, 1948. A, VISCHER, JR

FLEXIBLE COVER FORMING MACHINE Filed Aug. 1, 1945 7 Sheets-Sheet 6 Nov.23, 1948. A, WSC-HER, JR n 2,454,758 v FLEXIBLE covEE EORMING MACHINE'Filed Aug. l, 1945 7 Sheets-Sheet '7 Patented Nov. 23, 1948 FLEXIBLEFORMING MACHINE Alfred Vischer, Jr., Park Ridge,v Ill., assgnor, bymesne assignments, of 4twelve-thirtieths to Alfred Vischer, Jr.,two-thirtieths to William Vischer, two-thirtieths to Alfred Vischer,III, two-thirtieths to Alfred Vischer, Jr., as trustee, four-thirtiethsto Walter W. Zitzewitz, fourthirtieths to Elmer K.Zitzewitz,`onethirtieth Ato Gertrude J. Zitzewitz, one-thirtieth toBarbara 0. Zitzewitz, and two-thirtieths to Gertrude V. BoutonApplicationvAugust 1, 1945, Serial No. 608,105

s claims; (o1. 15s-54) My invention relates generally to flexible coverforming machines, and more particularly to' a machine for the quantityproduction of flexible covers of the type disclosedin'my `prior PatentNo. 2,232,011. j

In themanufacture of the covers of pressure cookers of the type shown inthe aforesaid patent, some difficulty has been encountered in formingthe covers to render them flexible and to introduce the stressesnecessaryto cause the cover to snap from its closed to open position,and vice versa. In the. past, such stresses were. introduced by securingthe dished cover in the chuck of a lathe and applying theeiiing force.by means of rollers in the manner of a conventionalspinf ning operation.While such forming of the covers by a spinning process was practical forcovers of smaller diameters, it was inadequate for covers of largersize. Even though the lathe was equipped with special tools and fixturesfor applying the pressure through the rollers, it was found that theapplication of the torque to` the cover at its center tended, to distortthe shape of the cover, and Was therefore not satisfactory, especiallyfor covers of larger diameters. f

It is therefore an `object of the invention to provide an improved`machine for substantially automatically ,flexing covers of the typeshown in said patent, to introduce the necessary stresses andflexibility. l Y.

A further object is to provide an improved cover flexing machine inwhich the torque is applied to the cover near the peripheral edgethereof.

Other objects will appear from the following description, referencebeing had to the accompanying drawings, in which: l,

Fig. 1 is a plan `View of the machine;

Fig. 2 is an end elevational view thereof Figs. 3 and 4 are transversesectional views thereof, taken on the lines 3-3` and 4 4, respectively,of Fig. 1; y V

Figs. 5 and 6 are sectional ,viewsl of the gear drive, taken on thelines 5-5 and 6 6, respectively, of Fig. 7;

Fig. 7- is a. horizontal sectional view, ,tekenen l= 2 the plane of themain drive shaft, and showing particularly the means for operating thepressure hails;

Fig. Sis a horizontal sectional view showing the drive gearing;

Fig. 9 is a fragmentary sectional View showing the clutch trippingmechanism;

Figil) is a fragmentary sectional view, taken enfthe mi loq-m of Figi;and

Fig. 11n is a fragmentary sectional view, taken on the line Il-II ofFig. 2.

In general, `the purpose of the machine is to flexadished circular cover2l) of the general shape shown in full lines in Fig. 3, to the shapeshown in' dotted' lines in said figure, such lexure taking place Whilethe cover is rotating, and thus by cold Working removing and impartingstresses to the -coverwhich will render it exible and cause it to snapfrom its Warped to its relatively nat shape, and vice versa, uponrelease and applicat'io'njof the requisite forces at its center and atleast. two diametri'cally opposite points along its periphery.

` `The cover 2D is made of stainless steel, thus having :the necessaryelasticity and strength t0 serve" asa cover for pressure cookers, inwhich the aggregate force applied may be in the order of '2000 pounds.`j' `The machine comprises a'frame 22 preferably oifc'ast iron,]having abearing bracket 24 bolted thereto. The bracket 24 has a pair of bearings26 fora shaft 28. A double V belt pulley 30 is adapted to be coupled tothe shaft 28 by a suitable .clutch mechanism contained Within a housing321` `This clutch mechanism includes a stop lug 34 which,`ivhen arrestedby the end of a controlrod 36, declutches the pulley 3i) from thes'naftz's-.v p'

,'I'he. clutch control rod 35 is slidably mounted infapai'r of bearings`555 which are suitably mounted on the bearing portions 26 of thebracket 24. The -rodS has an operating knob Ml secured to one'.y endandis normally urged to the right (Fig. 2,), to cause-its end` to lieWithin the path of the stopwll, byte coil spring a2, compressed betweenone of the bearing blocks 38 and a collar 44, the latter being suitablysecured to the rod 36. The rod 36 also has a bushing 46 secured thereto,this bushing having a frusto conical latching portion 46 engageable in anotch 50 formed in a latch 52. The latch 52 is pivoted on a stud 54 andis biased to move counterclockwise (Fig. 2) by a tension spring 55.

The latch 62 has a sidewardly extending lug 58 adapted to be engaged bya clutch release arm 68 secured to the end of a shaft extension 62 onshaft |3l.

As shown most clearly in Fig. 8, the shaft 28 has frictional dragapplied thereto by a clamp 64 having a suitable liner 66 of leather orthe like. l'ihe clamp 64 is held from rotation by a projection 68thereof, which fits in a slot 10 formed in an anchor plate 12, thelatter being suitably secured to the bearing bracket 26. The degree offriction applied by the clamp 64 may be adjusted by means of a bolt 14.By virtue of the friction applied to the shaft 28 by the clamp 64, asmall load is continuously placed on the shaft 28 to assure properoperation of the clutch mechanism contained in the housing 32.

The shaft 28 has a drive pinion 16 (Fig. 8) pinned thereto, this pinionmeshing with a spur gear 18 pinned to a counter-shaft 80. The shaft 60is mounted in suitable bushed bearings 82, and has a bevel pinion 84pinned to the end thereof. The bevel pinion 84 meshes with a pair ofbevel gears 86, 8l', the gear 81 being pinned to a shaft 80, while thehub of the bevel gear 86 interlocks with a sleeve 90 which is rotatablymounted on the shaft 88. The sleeve 90 forms part of a driving roller9|, having an annulus 92 of suitable friction material, such as ber orcompacted fabric, clamped thereto by a pair of rings 94, 95, theclamping being effected by hollow head cap screws 96 threaded in theclamping ring 95. The sleeve 90 is maintained in interlocking engagementwith the bevel gear 86 by a collar 98 secured to the shaft 88.

As best shown in Fig. 1, a second driving roller 99 is provided by asleeve member |00 pinned to the shaft 88 and having its frictionallydriving annulus |02 clamped to the sleeve |00 by clamping rings |04,|05, the clamping pressure being applied by hollow head cap screws |06threaded in the flange of the sleeve |00. From the foregoing, it willappear that the friction driving rollers 9| and 99 will be driven inopposite directions.

The cover 20 to be flexed has a central perforation which is engaged bya locating pin |08 (Fig. 3) guided for vertical movement in a bushingI0. The bushing I is secured in the upper end of a pedestal ||2 formingpart of the frame 22, and the locating pin |08 is held in its uppermostposition by a compressed coil spring I4. The pedestal ||2 also providesa central support for the main shaft 88, a suitable bearing bushing ||6being secured in the pedestal ||2 by set screws I8. The upper end of thebushing l0 is chainfered to provide a bearing surface for the centralportion of the cover 20.

The cover 20 is adapted to be clamped against the driving rollers 9|,99, by a. pair of idler rollers |20, |2I, (Figs. 1 and 3). These idlerrollers are mounted for free rotation upon a shaft |22, the ends of theshaft being eccentric and suitably journaled in bearings |24, |25. Ahandle |26 is secured to the shaft |22 so that when it is swung from theposition in which it is shown in Fig. 3

idler rollers |20 and |2| will be moved close to the driving rollers 9|,99, so as to clamp the peripheral edge of the cover 20 between them, andthereby enable the driving rollers 9|, 99 to rotate the cover 20.

A pair of bails |28, |29 are suitably journaled on pins |30 and shaft|3I. The pins |30 are rigidly secured in the frame 22, while the shaft|3| (Fig. 9) is rotatable in the frame and is nonrotatably secured tothe bail |29 by a plate |32 which has a splined connection with the endof shaft |3l. The shaft |3| is formed integrally with its reduceddiameter end portion 62 which carries the clutch release arm 60.

Each of the balls |28, |29 has a gear segment |34 formed integrallytherewith at each end, these segmental gears being in mesh as shown inFig. 6; The bails are rocked upon their pivots by a link |36 (Figs. 3and 4), the link being pivoted to the bail |28 lby an eccentric stud |38which is locked in adjusted position by a set screw |40. The link |36 isheld in position by a lug |4| secured to the bail 28. The other endofthe link 36 has a large bore |42 (Fig. '1) to receive an eccentric|44, the link being held on the eccentric by a keeper plate |46. Theeccentric |44 is formed' integrally with a sleeve |48 which extendsthrough a suitable bearing opening in the frame 22, and has a platesplined thereto. An integral gear |52 is riveted to the plate |50. Asimilar internal gear |54 is secured to a fixed gear housing |56 and thelatter is closed by a plate |58 which is secured to the frame 22.

A pinion |60 meshes with both of the internal gears |52 and |54, beingmounted on an eccentric |62 which is pinned to the main shaft 88.Suitable anti-friction bearing assemblies |64 are provided for thepinion |60. As illustrative, the internal gear |52 mayhave sixty teeth,while the internal gear |54 has fifty-fnine teeth, and the pinion |60may have fifty-six teeth. Thus, as the pinion |60 rolls around thestationary internal gear |54, it will cause the internal gear |52 torotate 1450 of a revolution for each revolution of the main shaft 88.

Each of the bails |28, |29 has a boss |66 near its center to receive a.bearing stud |68. A forming roller, comprising a bearing bushing |10and a fiber disc |12 clamped to the bushing |10 by side plates |14, ismounted for free rotation upon each of the studs |68. l

In forming a cover, the dished disc is placed in the position indicatedin full lines in Fig. 3, with the locating .pin |08 extending but ashort distance through the perforation at the center of the cover.Diametrically opposite portions near the edge of the cover rest upon thedriving rollers 9|, 99. The handle |26 is then swung to the position inwhich it is shown in Fig. 3, thereby, due to the eccentric mounting ofthe shaft |22, bringing the idler rollers |20, |2| into engagement withthe cover and pressing the latter firmly against the driving rollers 9|,99. The machine is then started by pulling on the knob 40 (Fig. 2) toremove the end portion of the rod 36 from engagement with the lug 34,thereby permitting the clutch lto operate and effect a drivingconnection between pulley 30 and the shaft 28. The rod 36 is latched inretracted position by the engagement of the conical portion 48 of thecollar 46 in the notch 50 of latch 52. The main shaft 88 is thus driventhrough the pinion 16, spur gear 18, bevel pinion 84 (Fig. 8) and bevelgear 81. The driving roller 9| is driven inl a ydirection opposite tothat of the shaft 88 aanwas through'the bevel gear 86. 'The cover,clamped against the-driving rollers 9|, 99, Ais thus rotated, and asitrotates the eccentric |44 (Fig. 7) isfrotated through the speed reducinggearing |52, |54, |60, at a speed 1&5@ of that of the `shaft 88. Thebails |28, |29 are thus slowly swung from the positions in which theyare shown in full lines in Fig. 3, successively to the positions inwhich they are shown in dotted lines'- The cover isY thereby flexedalong successive diameters to the intermediate and fully warped shapesin which it is-shownin dotted-lines in Fig. 3, such flexure beingaccomplished by the engagement of the forming rollers |12 with the cover2|) at substantially diametrically opposite points near the edgethereof. The flexure of the cover is continued as the bails |28, |29return to their normal positions, as shown in full lines in Fig. 3.

As the bails approach their normal positions, the arm 6|] (secured tothe end 62 of the shaft |3I, Fig. 9) engages the sidewardly extendinglug 58 (Fig. 2) of the latch 52, swinging the latter clockwise andpermitting the spring 42 to move the end of the rod 36 into position forengagement with the lug 34, thereby tripping the clutch within thehousing 32 and stopping the machine. After swinging the handle |28clockwise approximately 180 from the position in which it is shown inFig. 3, to disengage the idler rollers |20, |2|, the cover may beremoved from the machine, since now in its warped condition it easilyclears the locating pin |08.

It has been found that covers flexed in this machine are uniformlyworked to introduce stresses which give it the requisite properties tomake it snap to its closed position when it is used, and to cause it toassume a normally warped shape. This makes it possible for the cover tobe inserted in an inwardly flanged container having an opening of lesserdiameter than that of the cover, as more fully disclosed in my aforesaidpatent.

While I have shown and described a preferred embodiment of my invention,it will be apparent that numerous variations and modifications thereofmay be made without departing from the underlying principles of theinvention. I therefore desire, by the following claims, to includewithin the scope of the invention all such variations and modications bywhich substantially the results of my invention may be obtained throughthe use of substantially the same or equivalent means.

I claim:

1. In a machine of the class described, the combination of a pair ofspaced driving rollers, means to press a disc against said rollers tosecure frictional engagement therewith and thus to cause rotation of thedisc, a drive shaft, a train of gearing connecting said drive shaft tosaid rollers to cause the latter to rotate in opposite directions, apulley mounted on said drive shaft, a disengageable clutch connectingsaid pulley to the drive shaft, a manual control element, means forlatching said element in a position to cause engagement of the clutch, apair of forming rollers engageable with the upper surface of the disc atpoints near the periphery thereof and intermediate the points at whichthe driving roller engages the disc, means driven through said gearingfor swinging said forming rollers downwardly and inwardly with respectto the center of the disc thereby to bend the disc into inverted troughshape successively along angularly incremental y diameters asfthe discis rotated and thereafter t0 swing the forming rollers upwardly andoutwardly, and a latch releasing member operated by lsaid last namedmeans when the forming rollers have passed through a completeoscillatory cycle, thereby to release said manual control element andcause disengagement of said clutch.

2. In a machine of the classdescribed, a central vertically extendinglocating pin, a horizontal shaft beneath said locating pin, a drivingroller fixed to said shaft, a second driving roller rotatable on saidshaft, means for driving said rollers in oppositel directions a pair ofballs mounted for pivotal movement and interconnected so as to swing inopposite directions, an eccentric for swinging said bails, a speedreducing gearing connecting said eccentric and said shaft, a rollermounted for free rotation on each of said bails, a pair of idler rollersfor pressing a disc to be warped against said driving rollers, and meansfor moving said idler rollers toward said driving rollers to cause theidler rollers to press the disc against the driving rollers.

3. The combination set forth in claim 2, in which said speed reducinggearing for driving said eccentric comprises a fixed internal gear, arotatable internal gear connected to the eccentric, said internal gearsbeing of the same size but having different numbers of teeth, a pinionmeshing with both of said internal gears, and an eccentric connected tosaid shaft and forming a bearing for said pinion whereby said pinionwill roll around said internal gears and cause the movable internal gearto rotate through a small angle upon each revolution of the shaft.

4. In a machine of the class described, the combination of a pair ofdriving rollers, means for rotating said rollers at the same speed inopposite directions, idler rollers movable toward and away from saiddriving rollers for maintaining a cover to be formed in frictionalcontact with said driving rollers at diametrically opposite points ofthe cover, a pair of forming rollers engageable with a cover rotated bysaid driving rollers at substantially diametrically opposite points nearthe periphery of the cover and spaced intermediate the points at whichthe cover is engaged by the driving rollers, and means for swinging saidforming rollers inwardly and downwardly with respect to the center ofthe cover, thereby to warp the cover into a generally troughlike shapealong successive angularly incremental diameters as the cover is rotatedby the driving rollers.

5. In a machine for warping flexible generally circular covers, thecombination of means for gripping the cover at two diametricallyopposite spaced points and rotating the cover about a central polaraxis, a pair of elements engageable with the cover at substantiallydiametrically opposite points intermediate the points at which the coveris engaged by the gripping and rotating means, and means for swingingsaid elements downwardly and inwardly thereby to warp the cover into agenerally inverted trough-like shape as it is rotated by the drivingmeans.

6. In a machine for cold working generally circular flexible covers, thecombination of means for frictionally engaging the cover atdiametrically opposite points adjacent the edges thereof, said meansbeing driven to rotate the cover about its center, a pair of elementsengageable with said cover at points spaced substantially from thepoints at which said frictional means engage the cover, and means forslowly moving said ele- 7 ments downwardly and inwardly thereby to exsaid cover successfully about angularly incremental diameters as thecover rotates.

ALFRED VISCHER, JR.

REFERENCES CITED The -following references are of record in the l111e ofthis patent:

Kollberg July 4, 1899 Number Number 8 Name Date Hjorth Aug. 9, 1904Worth Sept. 19, 1911 Grin Apr. 16, 1918 Grotnes Oct. 26, 1926 Adams, Jr.May 6, 1930 Watkins Sept. 15, 1931 Cushwa et al. June 23, 1942 FOREIGNPATENTS Country Date Great Britain Mar. 17, 1920

